﻿//////////////////////////////////////////////////////////////////////////////
//
// Copyright © 1998-2024 Glodon Company Limited.
//
// Licensed under the MIT License
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the “Software”),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
//////////////////////////////////////////////////////////////////////////////

#pragma once

// std headers
#include <vector>
#include <map>

// qt headers
#include <QObject>

// gcmp headers

// custom headers


class QWidget;

namespace gmepgcs
{
    class PermissionWatcher : public QObject
    {
        Q_OBJECT

    private:
        explicit PermissionWatcher(QObject *parent = nullptr);
        PermissionWatcher(const PermissionWatcher &) = default;
        PermissionWatcher &operator=(const PermissionWatcher &) = default;
        virtual ~PermissionWatcher();

    public:
        static PermissionWatcher *Get();
        void CheckPermission();
        
        void Watch(QObject *target, void(*behavior)(QObject* targetObject, const int currentPermission));
        void Watch(QWidget *target, void(*behavior)(QWidget* targetWidget, const int currentPermission));

        template <typename Func>
        void OnCurrentPermissionChanged(Func handler);

        int GetCurrentPermission();

    public: // for test
        void TestSwitchPermission();

    signals:
        void CurrentPermissionChanged(const int oldPermission, const int newPermission);        

    private:
        void Init();

    private:
        static PermissionWatcher *s_pInstance;
        int m_currentPermission;
        std::vector<std::pair<QObject*, void(*)(QObject* targetObject, const int currentPermission)>> m_vWatchedObjectBehaviors;
        std::vector<std::pair<QWidget*, void(*)(QWidget* targetWidget, const int currentPermission)>> m_vWatchedWidgetBehaviors;
    };

    template<typename Func>
    inline void PermissionWatcher::OnCurrentPermissionChanged(Func handler)
    {
        connect(this, &PermissionWatcher::CurrentPermissionChanged, [=](const int oldPermission, const int newPermission) {
            handler(oldPermission, newPermission);
        });
    }
}